JP2010525936A - catalyst - Google Patents

Abstract

A method for producing a supported cobalt catalyst for Fischer-Tropsch synthesis, wherein in the first activation stage, a granular precursor of the catalyst is used with a reducing gas, at a first heating rate HR1, and at a temperature of the precursor. Treatment until reaching T ₁ (80 ° C. < T ₁ < 180 ° C.) to obtain a partially treated catalyst precursor. In the second activation stage, the partially treated catalyst precursor is reduced to a reducing property. The gas is used for a time t ₁ (where t ₁ is 0.1 to 20 hours) at a stepwise temperature increase x times at the second average heating rate HR2 (where 0 <HR2 <HR1). A partially reduced catalyst precursor is obtained, and in the third activation stage, the partially reduced catalyst precursor is reduced with a reducing gas at a third heating rate HR3 (where HR3> HR2). , Partially reduced catalyst precursor reaches temperature T ₂ And maintaining the temperature T ₂ for a time t ₂ (where t ₂ is 0 to 20 hours) to obtain an activated Fischer-Tropsch synthesis supported cobalt catalyst. how to.

Description

  The present invention relates to a catalyst. More particularly, the present invention relates to a method for activating a catalyst precursor to produce a supported cobalt catalyst for Fischer-Tropsch synthesis and the catalyst obtained by the method.

  As for supported cobalt catalysts for Fischer-Tropsch synthesis, it is well known to produce a precursor of this catalyst using a metal precursor and a particulate support. The production of the catalyst precursor involves many different catalyst production steps. The resulting catalyst precursor is then reduced using a reducing gas such as hydrogen in an activation process or step to obtain an activated Fischer-Tropsch synthesis supported catalyst.

In the known activation method, the catalyst precursor is reduced under a high-temperature hydrogen flow or a high-temperature hydrogen-containing gas flow. In the production of the supported cobalt catalyst for Fischer-Tropsch synthesis, the hydrogen reduction is 250%. It is preferably carried out at a temperature in the range of from 0 to 500 ° C., using a low pressure and a high gas linear velocity to minimize the vapor pressure of the production water that promotes the sintering of the reduced metal. It is well known that changing the method of reducing cobalt oxide to metallic cobalt affects the activity and selectivity of the resulting supported cobalt catalyst for Fischer-Tropsch synthesis. Specifically, U.S. Pat. No. 4,605,679 discloses that the activity of a cobalt catalyst can be increased by performing re-oxidation on the obtained catalyst after reduction in hydrogen and further performing re-reduction. US Pat. No. 5,292,705 shows that hydrogen reduction in the presence of a hydrocarbon liquid increases the initial Fischer-Tropsch synthesis performance of the resulting catalyst. US Pat. No. 5,585,316 describes that the oxidation of the catalyst first and then reduction with carbon monoxide increases the selectivity of the heavier Fischer-Tropsch reaction product. EP 1444040 describes a two-step reduction process with pure hydrogen against a catalyst precursor in which all reducible cobalt oxide species are represented by the formula unit CoO _a H _b (where a > 1.7, b> 0). Is disclosed to improve the economics of the reduction process without impairing the Fischer-Tropsch synthesis catalyst activity.

SUMMARY OF THE INVENTION An object of the present invention is to provide a supported cobalt catalyst for Fischer-Tropsch synthesis with high hydrocarbon synthesis activity. Such a catalyst can be obtained by the process of the present invention.

According to the present invention, a method for producing a supported cobalt catalyst for Fischer-Tropsch synthesis comprising:
In the first activation stage, a granular precursor of a supported cobalt catalyst for Fischer-Tropsch synthesis comprising a catalyst support impregnated with cobalt and containing cobalt oxide is first heated using a hydrogen-containing reducing gas or a nitrogen-containing gas. Treating at a rate HR1 until the precursor reaches a temperature T ₁ (where 80 ° C. < T ₁ < 180 ° C.) to obtain a partially treated catalyst precursor;
In the second activation stage, the partially treated catalyst precursor is used x times (where x is 1) at a second average heating rate HR2 (where 0 <HR2 <HR1) using a hydrogen-containing reducing gas. Treatment at time t ₁ (where t ₁ is 0.1 to 20 hours) with a stepwise temperature increase of an integer greater than) to obtain a partially reduced catalyst precursor, and
In the third activation stage, the partially reduced catalyst precursor is converted to a temperature T using a hydrogen-containing reducing gas at a third heating rate HR3 (where HR3> HR2). ₂ and maintained at temperature T ₂ for a time t ₂ (where t ₂ is 0 to 20 hours) to obtain an activated Fischer-Tropsch supported supported cobalt catalyst.
There is provided a method characterized by comprising:
In the present invention, the “average heating rate HR2” is defined as a value obtained by dividing the sum of the heating rates of each stepwise temperature rise by the number of stepwise temperature rises. “Stepwise temperature rise” is an increase in the heating rate. Where x is the number of stepwise increases in temperature and x is an integer greater than 1.

DETAILED DESCRIPTION OF THE INVENTION Surprisingly, it has been found that a supported cobalt catalyst for Fischer-Tropsch synthesis having high intrinsic activity can be obtained by subjecting the catalyst precursor to the reduction method (ie, activation method) of the present invention. .

  The treatment in the first activation stage, the second activation stage and the third activation stage can be performed at least in principle in any suitable manner in which the catalyst precursor and the reducing gas are brought into contact, for example Examples include a method in which a reducing gas as a fluidized medium is brought into contact with a fluidized bed of catalyst precursor particles, and a method in which a reducing gas is passed through and contacted with a fixed bed of catalyst precursor particles. However, a method using a fluidized bed is preferable.

In the first activation stage, first, the catalyst precursor is immediately treated with a hydrogen-containing reducing gas or a nitrogen-containing gas at the first heating rate HR1. The space velocity (SV1) of the gas in the first activation stage is preferably 1 < SV1 < 35 m ³ _n / reducible cobalt 1 kg / 1 hour, more preferably 3 < SV1 < 15 m ³ _n / reducible cobalt 1 kg. / 1 hour. “Reducible cobalt” means cobalt that is reducible under normal reducing conditions, for example, if the catalyst or catalyst precursor contains 20% by weight of cobalt and 50% of the cobalt is reducible, The amount of reducible cobalt is 0.1 g / g of catalyst or catalyst precursor. The first activation stage is continued until the precursor reaches temperature T ₁ .

The first heating rate HR1 is preferably satisfies 0.5 ° C. / min <HR1 <of 10 ° C. / min conditions, more preferably satisfies 1 ° C. / min <HR1 <of 2 ° C. / min conditions.

In the first activation stage, the temperature T ₁ may be T ₁ > 90 ° C. In one embodiment of the present invention, the temperature T ₁ is 120 ° C. < T ₁ < 150 ° C. In this embodiment, a slurry is prepared by preparing a granular catalyst carrier, a slurry of cobalt compound and water as precursor active components, impregnating the catalyst carrier with the cobalt compound, drying the impregnated catalyst carrier, and calcining the impregnated catalyst carrier. This is typically the case for the catalyst precursor obtained in the process.

The second activation phase begins when the catalyst precursor reaches temperature T ₁ and continues for time t ₁ as described above. The treatment time t ₁ in the second activation stage more preferably satisfies the condition of 1 hour < t ₁ < 10 hours, and typically satisfies the condition of 2 hours < t ₁ < 6 hours.

In the second activation stage, the temperature is raised at least twice. Therefore, in the second activation stage, the catalyst precursor is heated to raise the temperature from at least T ₁ to temperature T _H (where T _H > T ₁ and T _H <200 ° C.) at least twice. Line and process for time t ₁ . When the temperature is raised twice, x = 2, when the temperature is raised three times, x = 3, and so on. Thus, the heating rate will be different for each temperature increase. For example, when the heating rate in the first temperature increase is 1 ° C./min, the heating rate in the second temperature increase can be 2 ° C./min. Further, if desired, the catalyst precursor may be maintained for some time after a certain temperature increase and before the next temperature increase starts, at the temperature reached at the end of the certain temperature increase.

The third activation phase begins at the end of time t ₁ . Thus, at the start of the third activation stage, the catalyst precursor has a temperature T _H. The third activation stage continues until the temperature in the third treatment stage, ie the temperature of the activated Fischer-Tropsch synthesis catalyst, reaches temperature T ₂ . Preferably, the temperature T ₂ satisfies the condition of 300 ° C. < T ₂ < 600 ° C. More preferably, the temperature T ₂ is in the range of 300 ° C. to 500 ° C., and typically the temperature T ₂ is in the range of 300 ° C. to 450 ° C. The catalyst can be maintained at temperature T ₂ for a time t ₂ (where t ₂ is 0 to 20 hours), preferably the time t ₂ satisfies the condition of 0 hour <t ₂ < 20 hours, more preferably The time t ₂ satisfies the condition of 1 hour < t ₂ < 10 hours, and the time t ₂ typically satisfies the condition of 2 hours < t ₂ < 6 hours.

  In the second activation stage, the gas also has a space velocity (hereinafter referred to as “SV2”), and in the third activation stage, the gas also has a space velocity (hereinafter referred to as “SV3”).

  In one aspect of the invention, SV1, SV2 and / or SV3 may be constant in the processing of each activation stage. For example, the relationship between the space velocities in these activation stages may be SV1 = SV2 = SV3. However, in another embodiment of the invention, SV1, SV2 and SV3 may be different at each activation stage.

In the first activation stage, it is preferable to use a hydrogen-containing reducing gas, and the gases used in the three activation stages may have the same composition. “Hydrogen-containing reducing gas” means a hydrogen-containing mixed gas, and the hydrogen content H ₂ of the hydrogen-containing mixed gas satisfies 10% by volume <H ₂ < 100% by volume, more preferably the hydrogen-containing mixed gas. Consists of more than 90% by volume H ₂ and less than 10% by volume inert gas, most preferably more than 97% by volume H ₂ and less than 3% by volume inert gas. The inert gas may be any combination of Ar, He, NH ₃ and H ₂ O, and the dew point of the hydrogen-containing reducing gas is preferably 4 ° C. or less, more preferably −30 ° C. or less.

In the first activation stage, a nitrogen-containing gas can be used instead of the hydrogen-containing reducing gas. “Nitrogen-containing gas” means a mixed gas composed of N ₂ exceeding 90% by volume and other components less than 10% by volume. The other component may be any combination of Ar, He, and H ₂ O. The dew point of the nitrogen-containing gas is preferably 4 ° C. or lower, more preferably −30 ° C. or lower. The nitrogen-containing gas does not contain any hydrogen (ie hydrogen = 0% by volume).

  The processes of the first activation stage, the second activation stage, and the third activation stage may be performed under the same pressure, may be performed under different pressures, or both are performed at approximately atmospheric pressure. Preferably, both may be carried out under a pressure of 0.6 to 1.3 bar (absolute pressure).

  The supported cobalt catalyst precursor particles for Fischer-Tropsch synthesis (FTS) can be any suitable catalyst precursor that can be activated (ie, reduced) to yield an activated Fischer-Tropsch synthesis catalyst. The catalyst may be obtained during the production of the catalyst or may be obtained from a regenerated catalyst (hereinafter often referred to as “Fischer-Tropsch synthesis” as “FTS”).

  Thus, the catalyst precursor may be obtained during the production of a fresh catalyst, i.e., a slurry of a granular catalyst carrier, a cobalt compound as a precursor active component and water, and impregnating the catalyst carrier with the cobalt compound. The catalyst precursor containing cobalt oxide obtained by a production method by drying the impregnated catalyst carrier and calcining the impregnated catalyst carrier may be used. However, the catalyst precursor thus obtained cannot be used as a catalyst for the Fischer-Tropsch reaction without activation (ie, reduction), and this activation (ie, reduction) is used as a method of the present invention. To do. The catalyst thus obtained is an activated Fischer-Tropsch synthesis catalyst.

  The regenerated catalyst precursor can be obtained by regenerating a spent Fischer-Tropsch synthesis cobalt catalyst used for a certain period of time in the FTS method. As the regeneration method, any suitable regeneration method capable of obtaining an oxide catalyst precursor containing supported cobalt oxide can be used.

A commercially available shaped porous oxide catalyst support may be used. Examples thereof include alumina (Al ₂ O ₃ ), silica (SiO ₂ ), titania (TiO ₂ ), magnesia (MgO), SiO ₂ —Al ₂ O ₃ , and tin oxide (ZnO). The average pore diameter of the catalyst support is preferably 8 to 50 nanometers, more preferably 10 to 15 nanometers. The pore volume of the catalyst support may be 0.1 to 1.5 ml / g, preferably 0.3 to 0.9 ml / g.

  The catalyst support may be a protected modified catalyst support and may contain, for example, silicon as a modifying component. Examples of protected modified catalyst supports include those generally described in EP Patent Application No. 99066328.2 (EP Publication No. 1058580), which is hereby incorporated herein by reference. Incorporated in the description).

  More specifically, the protected modified catalyst carrier includes a silicon precursor such as an organic silicon compound (tetraethoxysilane (TEOS), tetramethoxysilane (TMOS), etc.) by an impregnation method, a deposition method, a chemical vapor deposition method, or the like. A silicon-containing modified catalyst carrier is obtained by contacting with a catalyst carrier, and the obtained silicon-containing modified catalyst carrier is obtained at a temperature of 100 ° C. to 800 ° C., preferably 450 ° C. to 550 ° C. for 1 minute to 12 hours in a rotary furnace or the like. Preferably, those obtained by calcining for 0.5 to 4 hours can be mentioned.

  The supported amount of cobalt may be in the range of 5 g of cobalt / 100 g of support to 70 g of cobalt / 100 g of support, and preferably in the range of 20 g of cobalt / 100 g of support to 55 g of cobalt / 100 g of support.

Specifically, the cobalt salt may be cobalt nitrate, that is, Co (No ₃ ) ₂ .6H ₂ O.

  Impregnation of the catalyst support can in principle be carried out by any known method or procedure. For example, it can be performed by an incipient wetness impregnation method or a slurry impregnation method. Therefore, impregnation of the catalyst support may be performed by the method described in, for example, US Pat. No. 6,455,462 and US Pat. No. 5,733,839 (these patent documents are incorporated herein by reference). .

  More specifically, the impregnation is performed by, for example, slurry containing a granular catalyst carrier, water and a cobalt salt at a high temperature under a pressure equal to or lower than atmospheric pressure (for example, 5 kPa (absolute pressure), preferably atmospheric pressure to 10 kPa (absolute pressure)). And the obtained impregnated support may be dried by drying at a high temperature under a pressure equal to or lower than the above atmospheric pressure. More specifically, in the impregnation, for example, in the initial stage of the treatment, the support is impregnated with the cobalt salt by placing the slurry at a high temperature under the pressure below the atmospheric pressure, and partially impregnating the resulting impregnated support. To obtain a partially dry impregnated support, and then, in a later stage of processing, the partially dried impregnated support is placed at a high temperature under the pressure below the above atmospheric pressure, in the latter stage of processing. By making the temperature higher than the temperature in the initial stage of processing and / or lowering the pressure in the late stage of processing lower than the pressure in the initial stage of processing, Alternatively, the impregnated carrier may be rapidly dried to obtain a dry impregnated carrier.

  As for the impregnation, the catalyst support can be impregnated in two stages or three or more stages to obtain a desired cobalt loading. Each impregnation step can include an initial stage of processing and a later stage of processing as described above.

  In the method of the present invention, the drying rate of the slurry can be controlled in each impregnation step so as to obtain a specific drying profile.

  For impregnation of the catalyst support, a 2-step slurry phase impregnation process can be used depending on the desired cobalt loading and the pore volume of the support.

  The impregnation and drying of the catalyst carrier can typically be performed using a conical vacuum dryer having a rotary screw or a rotary vacuum dryer.

  In the process of impregnation with cobalt, a water-soluble precursor salt of platinum (Pt), palladium (Pd), ruthenium (Ru), rhenium (Re) or a mixture thereof is added as a dopant capable of enhancing the reducibility of the active ingredient. May be.

  In order to calcine the impregnated and dried raw material, any method known to those skilled in the art may be used. For example, it may be performed at 200 ° C. to 400 ° C. using a fluidized bed, a rotary furnace, a calciner, or the like. Specifically, it may be carried out by the method described in WO 01/39882 (this patent document is incorporated herein by reference).

  The present invention also provides a catalyst for activated Fischer-Tropsch synthesis obtained by the process of the present invention.

The activated Fischer-Tropsch synthesis catalyst can be used in a hydrocarbon production process. A method for producing hydrocarbons using an activated Fischer-Tropsch synthesis catalyst comprises synthesizing hydrogen (H ₂ ) and carbon monoxide (CO) at a high temperature of 180 ° C. to 250 ° C. and a pressure of 10 to 40 bar. In which the Fischer-Tropsch reaction of hydrogen and carbon monoxide is carried out by contacting with the activated Fischer-Tropsch synthesis catalyst described above.

  The present invention will be described in more detail with reference to the following examples, which are not intended to limit the scope of the present invention.

Granularity of a supported cobalt catalyst for Fischer-Tropsch synthesis which upon activation forms a slurry phase Fischer-Tropsch synthesis catalyst (owned by the applicant) with a composition of 30 g Co / 0.075 g Pt / 1.5 g Si / 100 g Al ₂ O ₃ A precursor was used. This particulate catalyst precursor is described in detail in WO 01/39882.

A representative batch of this pre-reduced catalyst precursor was prepared by the following procedure. Puralox SCCa 2/150 (pore volume 0.48 ml / g) (manufactured by SASOL Germany GmbH, Hamburg 22297, Überselling 40, Germany) is modified with silicon to a final silicon level of 2.5 Si atoms / carrier nm ² to be. TEOS (tetraethoxysilane) was added to ethanol, alumina was added to the resulting solution (ethanol 1 liter / alumina 1 kg), and the resulting mixture was stirred at 60 ° C. for 30 minutes. The solvent was then removed under vacuum with a jacket temperature of 95 ° C. in the dryer. The obtained dry modified carrier was calcined at 500 ° C. for 2 hours. A solution comprising 17.4 kg of Co (NO ₃ ) ₂ .6H ₂ O, 9.6 g of (NH ₃ ) ₄ Pt (NO ₃ ) ₂ , and 11 kg of distilled water was prepared, and 20.0 kg of the silica modified product was prepared. Gamma-alumina support was added to this solution. The resulting slurry was placed in a conical vacuum dryer and continued to mix. After raising the temperature of the slurry to 60 ° C., the slurry was pressurized to 20 kPa (absolute pressure). During the first 3 hours of the drying process, the temperature was gradually increased to reach 95 ° C. after 3 hours. After 3 hours, the pressure was lowered to 3 to 15 kPa (absolute pressure), and the drying speed at the time of the initial wet impregnation method was set to 2.5 m% / 1 hour. It took 9 hours to complete the impregnation and drying, and then the impregnated dry catalyst support was immediately put into a fluid bed calciner. The temperature of the dry impregnated catalyst carrier when it was put into the calciner was about 75 ° C. The introduction into the calciner took about 1 to 2 minutes, and the internal temperature of the calciner was maintained at a preset temperature of about 75 ° C. Heat the dry impregnated catalyst carrier to 75 ° C to 250 ° C (heating rate is 0.5 ° C / min, air space velocity is 1.0m ³ _n / Co (NO ₃ ) ₂ · 6H ₂ O 1 kg / 1 hour), and then maintained at 250 ° C. for 6 hours. In order to obtain a catalyst with a cobalt loading of 30 g Co / 100 g Al ₂ O _3, a second impregnation / drying / calcination step was performed. Prepare a solution consisting of 9.4 kg Co (NO ₃ ) ₂ · 6H ₂ O, 15.7 g (NH ₃ ) ₄ Pt (NO ₃ ) ₂ , and 15.1 kg distilled water, 20.0 kg of the calcined catalyst precursor was added to this solution. The resulting slurry was placed in a conical vacuum dryer and continued to mix. After raising the temperature of the slurry to 60 ° C., the slurry was pressurized to 20 kPa (absolute pressure). During the first 3 hours of the drying process, the temperature was gradually increased to reach 95 ° C. after 3 hours. After 3 hours, the pressure was lowered to 3 to 15 kPa (absolute pressure), and the drying speed at the time of the initial wet impregnation method was set to 2.5 m% / 1 hour. It took 9 hours to complete the impregnation and drying, and then the treated catalyst support was immediately put into a fluid bed calciner. The temperature of the dry impregnated catalyst carrier when it was put into the calciner was about 75 ° C. The introduction into the calciner took about 1 to 2 minutes, and the internal temperature of the calciner was maintained at a preset temperature of about 75 ° C. Heat the dry impregnated catalyst carrier to 75 ° C to 250 ° C (heating rate is 0.5 ° C / min, air space velocity is 1.0m ³ _n / Co (NO ₃ ) ₂ · 6H ₂ O 1 kg / 1 hour), and then maintained at 250 ° C. for 6 hours. Thus, an alumina carrier-supported cobalt catalyst precursor was obtained.

  One sample of this catalyst precursor (named “catalyst precursor A”) was subjected to a standard one-step reduction process (ie, activation process) in the following procedure.

In the fluidized bed (inner diameter 20 mm) reduction unit, the catalyst precursor A is reduced under atmospheric pressure, and the undiluted H ₂ reducing gas (100% by volume H ₂ ) is used as the total supply gas, and the space velocity is 13. 7 m ³ _n / reducible cobalt 1 kg / 1 hour, and the following temperature program was used at the same time. Heat at a heating rate of 1 ° C./min to raise the temperature from 25 ° C. to 425 ° C., and maintain 425 ° C. for 16 hours.

  Thus, the catalyst precursor A was changed to the comparative catalyst A.

A three-step reduction process was performed on the other sample (named “catalyst precursor B”) of the catalyst precursor by the following procedure (Table 1).
(I) In the first activation stage, the sample is heated at a first heating rate of 1 ° C./minute to raise the temperature from 25 ° C. to 120 ° C., using pure 100% hydrogen,
(Ii) In the second activation stage, the sample is first maintained at 120 ° C. for 3 hours, then maintained at 130 ° C. for 3 hours, and then maintained at 140 ° C. for 3 hours;
(Iii) In the third activation stage, the sample is heated at a heating rate of 1 ° C./min to raise the temperature from 140 ° C. to 425 ° C., and the same space velocity as in the first activation stage and the second activation stage. And then maintained at 425 ° C. for 4 hours.

The reduction treatment was carried out in the fluidized bed reduction unit, and undiluted H ₂ reducing gas (100 volume% H ₂ ) was used in any of the three activation stages. In all three activation stages, pure 100% hydrogen was used and the space velocity was 13.7 m ³ _n / reducible cobalt 1 kg / 1 hour.

  Thus, the catalyst precursor B was subjected to the three-stage reduction / activation treatment of the present invention to obtain a catalyst B which is the catalyst of the present invention.

During the reduction, catalyst precursor A and catalyst precursor B were converted to catalyst A and catalyst B for Fischer-Tropsch synthesis (FTS), respectively. These catalysts are used in a laboratory scale reactor with realistic FTS conditions (230 ° C., pressure 17.5 bar (gauge pressure), H ₂ : CO inlet ratio 1.9: 1, The inert gas content of the gas is 15% (thus 85% of the inlet gas consists of H ₂ and CO), the space velocity of the synthesis gas is 7000 ml / 1 g / 1 hour, and the synthesis gas conversion is 50% to 65%. ).

RIAF = R elative I ntrinsic Fischer- Tropsch synthesis A ctivity F actor ( relative Fischer - Tropsch synthesis activity factor)

  From the above Table 1 (RIAF data), the activity one day after the start of the treatment of the catalyst B (experiment CB034) reduced by the three-step reduction treatment of the present invention is the activity of the catalyst A (experiment 198 £) reduced by the standard method. It is clear that it is significantly higher than

The “relative Fischer-Tropsch synthesis activator” (RIAF _X ) of a supported cobalt slurry phase catalyst produced using a pre-reduced catalyst precursor (ie, catalyst precursor X) produced in strict accordance with a given catalyst production procedure X is Define as follows.
RIAF _x = [A _xi / A _X ] (1)
In the formula:

a) A _xi is the Arrhenius pre-exponential factor of the catalyst precursor X activated according to any reduction procedure.

b) A _X, for activated catalyst precursor X according to standard 1-step reduction procedure described below, slurry phase continuous stirred tank reactors (C ontinuous S tirred T ank R eactor (CSTR)) Fischer - Tropsch synthesis Is a pre-Arrhenius exponent term estimated by continuously performing for 15 hours under realistic conditions.
Standard one-step reduction procedure: 15 ± 5 g of catalyst precursor A (ie prereduced catalyst mass) is reduced in a fluidized bed (inner diameter 20 mm) at atmospheric pressure. At that time, undiluted H ₂ reducing gas (purity 5.0) is used as the total supply gas, and the space velocity is 13700 ml. _n / reducible cobalt 1 g / 1 hour, and the following temperature program was used at the same time. Heat at a heating rate of 1 ° C./min to raise the temperature from 25 ° C. to 425 ° C., and maintain 425 ° C. for 16 hours.

c) The Arrhenius pre-exponential term A that applies to both A _xi and A _X is defined from the following experimental kinetic equation for a generally accepted cobalt-containing Fischer-Tropsch synthesis catalyst.
r _FT = [Ae ^{(-Ea / RT)} P _H2 P _CO ] / [1 + KP _CO ] ² (2)

Therefore, the pre-Arrhenius exponent term A is defined as follows.
A = [r _FT (1 + KP _CO ) ² ] / [e ^{(-Ea / RT)} P _H2 P _CO ] (3)
In the formula:
r _FT is the number of moles of CO converted to Fischer-Tropsch synthesis product / unit time / unit mass of the catalyst precursor in the prereduced state.

d) x represents a catalyst precursor.

Claims (12)

A method for producing a supported cobalt catalyst for Fischer-Tropsch synthesis comprising:
In the first activation stage, a granular precursor of a supported cobalt catalyst for Fischer-Tropsch synthesis comprising a catalyst support impregnated with cobalt and containing cobalt oxide is first heated using a hydrogen-containing reducing gas or a nitrogen-containing gas. Treating at a rate HR1 until the precursor reaches temperature T ₁ (where 80 ° C. < T ₁ < 180 ° C.) to obtain a partially treated catalyst precursor;
In the second activation stage, the partially treated catalyst precursor is used x times (where x is 1) at a second average heating rate HR2 (where 0 <HR2 <HR1) using a hydrogen-containing reducing gas. Treatment at time t ₁ (where t ₁ is 0.1 to 20 hours) with a stepwise temperature increase of an integer greater than) to obtain a partially reduced catalyst precursor, and
In the third activation stage, the partially reduced catalyst precursor is converted to a temperature T using a hydrogen-containing reducing gas at a third heating rate HR3 (where HR3> HR2). ₂ and maintained at temperature T ₂ for a time t ₂ (where t ₂ is 0 to 20 hours) to obtain an activated Fischer-Tropsch supported supported cobalt catalyst.
A method comprising: The method according to claim 1, wherein, in the first activation stage, the first heating rate HR1 satisfies a condition of 0.5 ° C / min < HR1 < 10 ° C / min. The method according to claim 2, wherein in the first activation stage, the first heating rate HR1 satisfies a condition of 1 ° C / min < HR1 < 2 ° C / min. 4. The method according to claim 1, wherein in the second activation stage, the time t ₁ satisfies a condition of 1 hour < t ₁ < 10 hours. 5. The method according to claim 4, wherein in the second activation stage, the time t ₁ satisfies a condition of 2 hours < t ₁ < 6 hours. In the second activation stage, by heating the catalyst precursor to a temperature T _H of the temperature T ₁ (where T _H> T _1, and, T _H <200 ° C.) of claim 1, wherein the The method according to any one. The method according to claim 1, wherein the temperature T ₂ satisfies a condition of 300 ° C. < T ₂ < 600 ° C. in the third activation stage. 8. The method according to claim 1, wherein in the third activation stage, the time t ₂ satisfies a condition of 1 hour < t ₂ < 10 hours.   9. The method according to claim 1, wherein the space velocity of the gas is constant in the processing of the first activation stage, the second activation stage and the third activation stage.   10. The first activation stage, the second activation stage, and the third activation stage are all performed under a pressure of 0.6 to 1.3 bar (absolute pressure). The method in any one of. A hydrogen-containing reducing gas is used in the first activation stage, and the hydrogen-containing reducing gas in each activation stage is composed of more than 90% by volume H ₂ and less than 10% by volume inert gas. Item 11. The method according to any one of Items 1 to 10. The process according to claim 1, characterized in that the hydrogen-containing reducing gas in each activation stage consists of more than 97% by volume H ₂ and less than 3% by volume inert gas.